Add isAvailable flag to RollbackData.

To distinguish between rollbacks of staged sessions before and after the
session has been applied.

Bug: 112431924
Test: atest RollbackTest
Change-Id: I93d6af4836933c0b551e17479ec896639ca0740e

services/core/java/com/android/server/rollback/RollbackData.java

@@ -55,6 +55,14 @@ class RollbackData {
      */
     public int stagedSessionId;
 
+    /**
+     * A flag to indicate whether the rollback should be considered available
+     * for use. This will always be true for rollbacks of non-staged sessions.
+     * For rollbacks of staged sessions, this is not set to true until after
+     * the staged session has been applied.
+     */
+    public boolean isAvailable;
+
     /**
      * Whether this Rollback is currently in progress. This field is true from the point
      * we commit a {@code PackageInstaller} session containing these packages to the point the
@@ -63,10 +71,11 @@ class RollbackData {
     // NOTE: All accesses to this field are from the RollbackManager handler thread.
     public boolean inProgress = false;
 
-    RollbackData(int rollbackId, File backupDir, int stagedSessionId) {
+    RollbackData(int rollbackId, File backupDir, int stagedSessionId, boolean isAvailable) {
         this.rollbackId = rollbackId;
         this.backupDir = backupDir;
         this.stagedSessionId = stagedSessionId;
+        this.isAvailable = isAvailable;
     }
 
     /**

services/core/java/com/android/server/rollback/RollbackManagerServiceImpl.java

@@ -221,7 +221,10 @@ class RollbackManagerServiceImpl extends IRollbackManager.Stub {
             List<RollbackInfo> rollbacks = new ArrayList<>();
             for (int i = 0; i < mAvailableRollbacks.size(); ++i) {
                 RollbackData data = mAvailableRollbacks.get(i);
-                rollbacks.add(new RollbackInfo(data.rollbackId, data.packages, data.isStaged()));
+                if (data.isAvailable) {
+                    rollbacks.add(new RollbackInfo(data.rollbackId,
+                                data.packages, data.isStaged()));
+                }
             }
             return new ParceledListSlice<>(rollbacks);
         }
@@ -655,6 +658,10 @@ class RollbackManagerServiceImpl extends IRollbackManager.Stub {
             Iterator<RollbackData> iter = mAvailableRollbacks.iterator();
             while (iter.hasNext()) {
                 RollbackData data = iter.next();
+                if (!data.isAvailable) {
+                    continue;
+                }
+
                 if (!now.isBefore(data.timestamp.plusMillis(ROLLBACK_LIFETIME_DURATION_MILLIS))) {
                     iter.remove();
                     mRollbackStore.deleteAvailableRollback(data);
@@ -1064,7 +1071,7 @@ class RollbackManagerServiceImpl extends IRollbackManager.Stub {
             ensureRollbackDataLoadedLocked();
             for (int i = 0; i < mAvailableRollbacks.size(); ++i) {
                 RollbackData data = mAvailableRollbacks.get(i);
-                if (getPackageRollbackInfo(data, packageName) != null) {
+                if (data.isAvailable && getPackageRollbackInfo(data, packageName) != null) {
                     return data;
                 }
             }
@@ -1083,7 +1090,7 @@ class RollbackManagerServiceImpl extends IRollbackManager.Stub {
             ensureRollbackDataLoadedLocked();
             for (int i = 0; i < mAvailableRollbacks.size(); ++i) {
                 RollbackData data = mAvailableRollbacks.get(i);
-                if (data.rollbackId == rollbackId) {
+                if (data.isAvailable && data.rollbackId == rollbackId) {
                     return data;
                 }
             }

services/core/java/com/android/server/rollback/RollbackStore.java

@@ -201,13 +201,13 @@ class RollbackStore {
      */
     RollbackData createAvailableRollback(int rollbackId) throws IOException {
         File backupDir = new File(mAvailableRollbacksDir, Integer.toString(rollbackId));
-        return new RollbackData(rollbackId, backupDir, -1);
+        return new RollbackData(rollbackId, backupDir, -1, true);
     }
 
     RollbackData createPendingStagedRollback(int rollbackId, int stagedSessionId)
             throws IOException {
         File backupDir = new File(mAvailableRollbacksDir, Integer.toString(rollbackId));
-        return new RollbackData(rollbackId, backupDir, stagedSessionId);
+        return new RollbackData(rollbackId, backupDir, stagedSessionId, false);
     }
 
     /**
@@ -247,6 +247,7 @@ class RollbackStore {
             dataJson.put("packages", toJson(data.packages));
             dataJson.put("timestamp", data.timestamp.toString());
             dataJson.put("stagedSessionId", data.stagedSessionId);
+            dataJson.put("isAvailable", data.isAvailable);
 
             PrintWriter pw = new PrintWriter(new File(data.backupDir, "rollback.json"));
             pw.println(dataJson.toString());
@@ -307,8 +308,9 @@ class RollbackStore {
 
             int rollbackId = dataJson.getInt("rollbackId");
             int stagedSessionId = dataJson.getInt("stagedSessionId");
+            boolean isAvailable = dataJson.getBoolean("isAvailable");
             RollbackData data = new RollbackData(rollbackId, backupDir,
-                    stagedSessionId);
+                    stagedSessionId, isAvailable);
             data.packages.addAll(packageRollbackInfosFromJson(dataJson.getJSONArray("packages")));
             data.timestamp = Instant.parse(dataJson.getString("timestamp"));
             return data;

services/tests/servicestests/src/com/android/server/rollback/AppDataRollbackHelperTest.java

@@ -80,7 +80,7 @@ public class AppDataRollbackHelperTest {
     }
 
     private static RollbackData createInProgressRollbackData(String packageName) {
-        RollbackData data = new RollbackData(1, new File("/does/not/exist"), -1);
+        RollbackData data = new RollbackData(1, new File("/does/not/exist"), -1, true);
         data.packages.add(new PackageRollbackInfo(
                 new VersionedPackage(packageName, 1), new VersionedPackage(packageName, 1),
                 new IntArray(), new ArrayList<>(), false));